Characterisation and Modelling of Continuous-Discontinuous Sheet Moulding Compound Composites for Structural Applications
The main objective of this work is to significantly deepen the understanding of the material and the structural behaviour of continuous-discontinuous SMC composites, following a holistic approach to investigate microscopic aspects, macroscopic mechanical behaviour as well as failure evolution at the...
| Otros Autores: | |
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| Formato: | Libro electrónico |
| Idioma: | Inglés |
| Publicado: |
Karlsruhe :
KIT Scientific Publishing
2020.
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| Colección: | Schriftenreihe des Instituts für Angewandte Materialien, Karlsruher Institut für Technologie
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| Materias: | |
| Ver en Biblioteca Universitat Ramon Llull: | https://discovery.url.edu/permalink/34CSUC_URL/1im36ta/alma991009871126606719 |
Tabla de Contenidos:
- List of Figures xv
- List of Tables xxiii
- List of Abbreviations and Symbols xxv
- 1 Introduction. 1
- 1.1 Motivation . 1
- 1.2 Scope and objective. 5
- 1.3 Contribution to the current state of research. 6
- 1.4 Outline of this dissertation 8
- 2 Current state of research 9
- 2.1 Definition of hybrid materials 9
- 2.2 Composite materials . 14
- 2.2.1 Definition and fundamentals 14
- 2.2.2 Basic mechanisms of fibrous reinforcement. 16
- 2.3 Sheet moulding compound composites. 21
- 2.3.1 Definition and terminology delimitation 21
- 2.3.2 Discontinuous SMC composites 21
- 2.3.3 Continuous SMC composites 57
- 2.4 Hybrid composites . 61
- 2.4.1 Definition, motivation and development
- of hybrid composites . 62
- 2.4.2 Evaluation of hybridisation effects . 65
- 2.4.3 Existing concepts of hybrid SMC . 68
- 2.5 Research questions . 82
- 3 Materials and specimen geometries 85
- 3.1 Manufacturing of SMC composites 85
- 3.1.1 Composition of resin systems . 85
- 3.1.2 Manufacturing of semi-finished sheets 87
- 3.1.3 Manufacturing of compression moulded sheets . 89
- 3.1.4 Manufacturing of pure resin sheets 92
- 3.1.5 Manufacturing of demonstrator part 93
- 3.2 Specimen preparation and geometry 94
- 3.2.1 Water-jet cutting and milling 94
- 3.2.2 End tabs. 95
- 3.2.3 Specimen geometries . 95
- 4 Experimental setups, procedures and data evaluation 103
- 4.1 Characterisation strategy 103
- 4.2 Characterisation at the coupon level 105
- 4.2.1 Microstructural characterisation 105
- 4.2.2 Macrostructural characterisation . 106
- 4.3 Characterisation at the structure level. 114
- 4.3.1 Quasi-static puncture testing 114
- 4.3.2 Dynamic puncture testing . 116
- 4.4 Characterisation at the component level 118
- 4.5 Data evaluation . 121
- 5 Analytical modelling 123
- 5.1 Description of modelling approach 123
- 5.2 Micromechanics and homogenisation methods . 124
- 5.2.1 Fundamentals of homogenisation 124
- 5.2.2 Analytical modelling of fibre reinforced polymers 128
- 5.3 Classical laminate theory 133
- 5.3.1 Macromechanical characterisation of a lamina . 134
- 5.3.2 Macromechanical characterisation of a laminate. 134
- 5.4 Analytical modelling of hybrid composites 138
- 5.4.1 Rule of hybrid mixtures 139
- 5.4.2 Tensile and flexural modulus based on classical laminate theory . 140
- 6 Results . 143
- 6.1 Evaluation of testing methods and preliminary studies . 143
- 6.1.1 Tensile properties of discontinuous SMC composites . 144
- 6.1.2 Tensile properties of continuous SMC composites 150
- 6.1.3 Flexural properties of SMC composites . 152
- 6.2 Microstructural analysis . 158
- 6.2.1 Fibre volume content . 158
- 6.2.2 Fibre orientation distribution 164
- 6.2.3 Interface of continuous-discontinuous SMC 173
- 6.3 Mechanical properties and failure at the coupon level . 176
- 6.3.1 Tensile and compressive properties of
- polyester-polyurethane hybrid resin . 176
- 6.3.2 Process-induced material properties of
- discontinuous glass fibre SMC 179
- 6.3.3 In-plane loading of SMC composites 190
- 6.3.4 Out-of-plane loading of SMC composites . 229
- 6.4 Mechanical properties and failure at the structure level . 237
- 6.4.1 Puncture properties of discontinuous glass fibre SMC 238
- 6.4.2 Puncture properties of continuous carbon fibre SMC . 248
- 6.4.3 Puncture properties of continuous-discontinuous glass/carbon fibre SMC 256
- 6.5 Mechanical properties and failure at the component level . 268
- 6.6 Analytical stiffness prediction 271
- 6.6.1 Analytical stiffness prediction of discontinuous glass fibre SMC 272
- 6.6.2 Analytical stiffness prediction of continuous carbon fibre SMC . 277
- 6.6.3 Analytical stiffness prediction of continuous-discontinuous glass/carbon fibre SMC 279
- 7 Discussion. 283
- 7.1 Testing methodology and preliminary studies 283
- 7.2 Material behaviour of unsaturated polyester-polyurethane two-step curing hybrid resin system 285
- 7.3 Discontinuous glass fibre SMC . 287
- 7.3.1 Microstructural aspects of discontinuous glass fibre SMC 287
- 7.3.2 Mechanical behaviour and damage evolution of discontinuous glass fibre SMC . 291
- 7.4 Continuous carbon fibre SMC 301
- 7.4.1 Microstructural aspects of continuous carbon fibre SMC . 301
- 7.4.2 Mechanical behaviour and damage evolution of continuous carbon fibre SMC 302
- 7.5 Continuous-discontinuous glass/carbon fibre SMC 308
- 7.5.1 Microstructural aspects of continuous-discontinuous glass/carbon fibre SMC 308
- 7.5.2 Mechanical properties, damage evolution and hybridisation effect 310
- 8 Final remarks . 347
- 8.1 Summary . 347
- 8.2 Conclusion . 356
- Bibliography 361
- A Appendix 403
- A.1 Influence of subset size and step size . 403
- A.2 Influence of edge preparation 405
- A.3 Tensile properties of discontinuous glass fibre SMC (2D) . 406
- A.4 Tensile properties of discontinuous glass fibre SMC (1D) . 407
- A.5 Compressive properties of discontinuous glass fibre SMC . 408
- A.6 Tensile and compressive properties of continuous carbon fibre SMC . 409
- A.7 Flexural properties of continuous carbon fibre SMC. 410
- A.8 Flexural properties of continuous-discontinuous glass/carbon fibre SMC . 411
- A.9 Classical laminate theory: calculations 412.
